Commit 668e4147 authored Sep 02, 2021 by Yang Shi Committed by Linus Torvalds Sep 03, 2021

mm/vmscan: add page demotion counter

Account the number of demoted pages.

Add pgdemote_kswapd and pgdemote_direct VM counters showed in
/proc/vmstat.

[ daveh:
   - __count_vm_events() a bit, and made them look at the THP
     size directly rather than getting data from migrate_pages()
]

Link: https://lkml.kernel.org/r/20210721063926.3024591-5-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-6-ying.huang@intel.com


Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Wei Xu <weixugc@google.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 26aa2d19

include/linux/vm_event_item.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -33,6 +33,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
		PGREUSE,
		PGSTEAL_KSWAPD,
		PGSTEAL_DIRECT,
		PGDEMOTE_KSWAPD,
		PGDEMOTE_DIRECT,
		PGSCAN_KSWAPD,
		PGSCAN_DIRECT,
		PGSCAN_DIRECT_THROTTLE,

mm/vmscan.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -1318,6 +1318,11 @@ static unsigned int demote_page_list(struct list_head *demote_pages,
		target_nid, MIGRATE_ASYNC, MR_DEMOTION,
		&nr_succeeded);

		if (current_is_kswapd())
		__count_vm_events(PGDEMOTE_KSWAPD, nr_succeeded);
		else
		__count_vm_events(PGDEMOTE_DIRECT, nr_succeeded);

		return nr_succeeded;
		}

mm/vmstat.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1217,6 +1217,8 @@ const char * const vmstat_text[] = {
		"pgreuse",
		"pgsteal_kswapd",
		"pgsteal_direct",
		"pgdemote_kswapd",
		"pgdemote_direct",
		"pgscan_kswapd",
		"pgscan_direct",
		"pgscan_direct_throttle",